Piston cleaning apparatus



NOV. 4, 1952 L, LUFT 2,616,108

4 PISTON CLEANING APPARATUS Filed May 14, 1947 2 SHEETS-SHEET 1 Lawrence .L. luff Patented Nov. 4, 1952 UNITED STATES PATENT OFFICE PISTON CLEANING APPARATUS Lawrence L. Luft, Gahanna, Ohio Application May 14, 1947, Serial No. 747,931

1 Claim.

The present invention relates to apparatus. for holding and imparting axial rotation to internal combustion engine pistons undergoing cleaning operations.

.In the past, the cleaning or removal of carbon deposits from pistons, and particularly from the ring grooves formed therein, has been accomplished by means of various hand tools which where rotated or twisted about the piston while the latter was held fast within a vise or in the hand. Cleaning operations of this type were necessarily tedious and: time consuming, and 01- tentimes failed to completely clean or remove the tightly and firmly adhering carbon from the metallic surface of the piston, the same being substantially welded to the metal due to the extreme heat encountered during engine operations. In most instances, the failure to properly'remove such carbon deposits was occasioned by the inability of the tool operator to exert sufficient force upon the associated hand cutting tool due to the instability of the support of the piston.

Accordingly, it is an. object of this invention to provide a machine capable of holding, and at the same time imparting axial rotation to an engine piston while a cutting or cleaning tool is utilized to penetrate the ring grooves of the piston with sufiicient pressure to remove all carbon deposits disposed therein.

Itis another object of this invention to provide a machine: of the character described which opcrates at a relatively" high speed to eiiiciently clean a piston in a vastly decreased time relative to prior hand cleanin'g methods.

A further object of the present invention is to provide a machine of this character which is capable of cleaning substantially the entire outer surface of a piston in a single operation requiring but a fraction of the time necessary to clean a piston under previously known hand operations.

For a further and more detailed understanding of the present invention, reference is made to the following description and the accompanying drawings wherein:

Fig. 1 is a top plan view of a machine formed in accordance with thisinventi'on;

Fig. 2 is a side elevational view thereof;

Fig. 3. is an end elevational view thereof;

Fig. 4 is an enlarged vertical sectionalview taken along a plane. indicated by the line 4-5 of 3;.

Fig. 5 is a similar view taken along the line 5-4). of Fig; 4.;

Fig.6.1s a. side elevational view of. a hand-held cutting or cleaning tool used in conjunction with the machine;

Fig. '7 is an enlarged fragmentary top plan view of the tensioning roller embodied in the present invention.

With reference tothe drawings, it will be seen that the present invention makes use of a boxlike frame or cabinet H] which houses an electric motor II, the latter serving as a driving means for other mechanism embodied in the present invention, and to be hereinafter more fully described. Mounted upon the upper surface of the cabinet If), within suitable bearing collars I2, is a rotatable roller it, the same being disposed on a substantially horizontal plane and extending transversely of the cabinet. The roller I3 is provided with an axially disposed shaft M which carries substantially at its rearward end a belt-receiving wheel l5. Axial rotation is imparted to the roller l3 and its associated belt-receiving wheel [5' by means of a belt l5 driven by the electric motor H. A protective housing or guard I! is provided for the exposed portion of the wheel [5, and is suitably secured to the upper surface of the cabinet Ill". The driven roller I3 is advantageously faced with yieldable mate rial such as rubber, or various compositions thereof, in order that frictional engagement may obtain between the roller and an object coming in contact therewith.

Disposed adjacent the driven roller l3 inparallel spaced relation thereto, is an idler roller |-8 which is rotatably mounted within similar bearing collars Hi; The two rollers due to their spaced relation, provide a bed or cradle which is adapted to receive in longitudinal order a piston 20: of the type utilized in internal combustion engines associated with automative vehicles, and aircraft. As shown in the drawings, pistons of this type are generally provided or formed with a plurality of ring-receiving grooves 2| which, after sustained engine operation, become clogged or embedded with burnt carbon deposits" which reduce the overall efiiciency of an internal combustion engine by tending to lock the associated piston rings, and prevent free movement thereof with respect to the associated pistons. Upon overhaul of an associated internal combustion engine, it becomes necesssary to clean these grooves, as well as the exterior surfaces of the pistons to remove such carbon deposits therefrom; to this end the present machine has been formed to. facilitate the. cleaning. or removal of suchv carbon deposits. by providing? a mechanism capable of holding and at the" same time imparting rotation to the associated piston in order that a hand-held cleaning or cutting tool may be inserted within the associated grooves 2| to remove embedded carbon therefrom.

To provide the necessary holding force for the associated piston 20, an arm 22 is hingedly mounted within a stationary bracket 23 secured to the upper surface of the cabinet, and a second idler roller 24 is rotatably carried at the opposite end of the arm 22, and disposed above and in triangular relationship to the lower rollers l3 and I8. The idler roller 24 functions to impart the necessary holding force to the associated piston 20, and serves to force the same downwardly into engagement with the base rollers, whereupon rotation within the driven roller I3 is imparted to the associated piston. A bow spring 25 is connected to the upright bracket 23, and engages the inner end of the arm 22 in order to exert a resilient upward force thereto, normally tending to maintain the second idler roller 24 out of en gagement with the associated piston,'in order that sufficient clearance is provided for the insertion of the piston into the cradle formed by the base rollers. 7

A manually operable cam 26 is eccentrically pivoted, as at 21, to a bifurcated bracket 28 secured to the upper surface of the cabinet. The periphery of the cam wheel 26 is engageable with the upper surface of the arm 22, and upon swinging movement in one direction serves to force the same downwardly upon the outer surface of the piston 20, and conversely, by actuating the cam wheel 26 in the opposite direction, the arm 22 is allowed to swing upwardly under action of the bow spring 25, in order to release the idler roller 24 from the upper surface of the piston. It will be understood, that the dimensions of the cam wheel 26 serve to control the limitation upon the movement of the associated arm 22 and the clearance between the upper idler roller 24 and the base rollers 13 and I8, in order that various sizes of pistons may be positioned for cleaning within the machine.

It will be seen that the upper idler roller 24 is carried in a slight horizontal angular relation to the axis of the base rollers I3 and I8, and due to this angularity, the associated piston 20, during its rotation by the driven roller [3, is moved forwardly of the rollers to engage a hingedly mounted soraperblade 28. In this manner, the head or closed end of the piston is forced against the scrape blade, and as the former undergoes rotation, carbon deposits present upon the head of the pistons will be removed by the relatively sharp edge of the blade 28. This latter provision only applies in the cases of pistons having a flat head, and as shown in Fig. 7, pistons of the type formed with a beveled head or irregularhead surface, are maintained or prevented from sliding forwardly of the rollers by means of a swinging pintle 29, which is secured Within a collar 31! carried at the forward end of the rollers, and in this event the scraping blade, which is hingedly movable by means of a set screw 3|, is swung out of engagement with the piston head.

The upper surface of the cabinet I is provided with a slot disposed between the parallel rollers l3 and I8, and below this opening, the cabinet is provided with a dependent metallic strap 32 which forms a recess adapted for the reception of the base or handle portion of a wire brush 33, and interposed between the base portion of the brush and the bottom of the straps 32 are a pair of expansion springs 34 which normally urge the brush in an upward direction between the base rollers. As is the usual case, the brush 33 is provided with relatively long metallic bristles which are maintained in engagement with substantially the entire lowermost wall surface of the piston 23, and upon rotation of the latter, serves to abrasively clean and remove carbon deposits or burned areas from the exterior walls of the piston. It will be understood, that the brush 33, in such a condition, is subject to relatively extreme wear, hence the springs 34 serve to compensate for such wear by constantly urging the brush upwardly into engagement with the piston 20.

Fig. 6 of the drawings discloses a cutting or cleaning tool which may be advantageously used in conjunction with the present machine, and which generally comprises an elongated bar 35, which is held by hand, and which is further provided with a plurality of arcuate guide lips 33 and rearwardly disposed cleaning edges 31. The necessity for a plurality of these latter members is occasioned by the fact that the normal piston of an internal combustion engine is provided with a plurality of ring grooves of varying widths, and it is therefore necessary to provide separate cutting surfaces corresponding in widths to those of the grooves; the difference in widths of the ring grooves of the piston is shown particularly in Fig. 5 of the drawing. The arcuate guide lips 38 serve to position the cutting faces 31 in their proper position with respect to the associated grooves of the piston, and prevent the same from cutting too deeply into the piston surface, or from widening the ring-receiving grooves. It will be understood however, that the present invention is not necessarily limited to the type of cutting tools used, but has as its objective, the provision of a rigid and rotating support for a piston undergoing cleaning operations, it being understandable that considerable pressure must be exerted upon the associated hand tool in order to efficiently remove carbon deposits from the piston.

In view of the foregoing, it will be seen that the present invention provides a highly useful and mechanically eflicient machine for holding and imparting rotation to pistons undergoing cleaning operations. Through actual use, it has been found that the overall cleaning time of a piston is greatly reduced through utilization of this machine, by reason of the fact that the entire outer surface of the piston undergoes cleaning in substantially a single operation, with the brush serving to clean and buff the outer walls, the scraper, the head of the piston, and the associated hand tool, the grooves thereof. The invention is further characterized by its structural simplicity, its ease of operation, and its economy of manufacture.

While a preferred embodiment of the present invention has been disclosed in detail, it will be manifest that various modifications as to details of construction and design may be accomplished without departing from the spirit of the invention or the scope of the following claim.

I claim:

A machine for simultaneously holding and rotating an internal combustion engine piston of the type having a grooved head portion and an ungrooved skirt portion comprising a frame, a pair of spaced cylindrical rollers rotatably mounted on said frame to cradle a piston therebetween, means to rotate one of said rollers, an arm pivot ally connected at one end to said frame for limited swinging movement in a vertical plane and having its opposite end extending over-said rollers, spring means to urge said arm to swingin a pair of rollers for wiping engagement with the direction away from said rollers, a third roll outer walls of a piston cradled in said pair of shorter than saidjflrst pair of rollers carried rollers. the opposite endof said arm for engagement w the skirt portion only of a piston cradled in s first pair of rollers, said third roller beingffar. ranged in obliql angular relation to the axes} LAWRENCE L. LUFT.

REFERENCES CITED The following references arefQf-record in the file of this-patent: '2

rollers, means carried by s d 10 UNITED STATES PArEnTs to one end of said first pair Number Name Date of rollers to eng e an end of a piston cradled n; 627,272 Schmidt June 20, 1899 Said Pair of l -P i r bifurcated rt 1,663,671 Sundstrand Mar. 27, 1923 bracket carried by aid frame and extending; 1,770,201 Eaton July 8' 1930 v 3 gr said g g c 2,012,715 Boone .."'Aug. 27, 1935 mounted dlsc carr e y said racke an angel able with said am to move the latter in a dir FOREIGN PATENTS tion to engage" said third roller with a pist'q Number Country Date cradled in said first pair of rollers, and a sprl' 272,337 rm ny Mar. 30, 1914 pressed brush carried by said frame between sa 7 20 397,633 Germany June 1924 

